Ice skateboards are often used outdoors on natural ice of a frozen pond, lake or river, and on sidewalks and in parking lots following a winter storm of freezing rain for example. These icy surfaces are normally harder than the artificial ice of an arena. Natural ice is also known to have a pebbly surface comprising frozen lumps, cracks and hollows. The irregular surfaces and the hardness of natural ice cause vibration stresses and associated deterioration to the structure of an ice skateboard. These vibration stresses are also known to increase fatigue of the user of the skateboard.
Each truck of a conventional roller skateboard usually has a resilient shock-absorbing member at the center thereof for acting simultaneously on both wheels on that truck. Although this arrangement is practical for use of roller skateboards, there are numerous advantages of having each blade of a four-runner ice skateboard independently cushioned. Some of these advantages are better stability, maneuverability and a smoother ride.
Examples of skateboards of the prior art for use on hard snow and ice are disclosed in the following documents:
U.S. Pat. No. 4,114,913 issued on Sep. 19, 1978 to W. K. Newell et al.; PA1 U.S. Pat. No. 4,165,091 issued on Aug. 21, 1979 to D. E. Chadwick; PA1 U.S. Pat. No. 4,194,753 issued on Mar. 25, 1980 to D. Schrishuhn, Jr.; PA1 U.S. Pat. No. 4,225,145 issued on Sep. 30, 1980 to R. K. Carr; PA1 U.S. Pat. No. 4,521,029 issued on Jun. 4, 1985 to T. L. Mayes; PA1 U.S. Pat. No. 4,896,893 issued on Jan. 30, 1990 to A. A. Shumays et al.; PA1 U.S. Pat. No. 5,161,810 issued on Nov. 10, 1992 to J. J. DeCesare.
Although these prior inventions deserve undeniable merits, there is no known prior art which provides for individual cushioning of the blades of an ice skateboard.
Therefore it is believed that there continues to be a need for a skateboard runner which has shock absorbing features incorporated therein, which is easily mountable to the truck axle of a roller skateboard and wherein the alignment of the blade relative the truck axle is maintainable at all times. Further, it is believed that there continues to be a need for a skateboard runner from which the blade is easily demountable for sharpening or for replacement.